Effect of Substrate Temperature on the Properties of Vacuum Evaporated Thin InSb Films

Abstract

Indium Antimonide (InSb) thin films weredeposited onto well cleaned glass substrate at differentsubstrate temperatures (323K, 373K and 473K) byvacuum evaporation technique using InSb compound asa source material. The characteristics of the films suchas composition, microstructure and electrical propertieswere investigated in terms of substrate temperature. X-ray diffraction studies confirmed the polycrystallinity ofthe films and the films show preferential orientationalong the (111) plane. The particle size, dislocationdensity and strain were evaluated. The particle sizeincreases with the increase of substrate temperature,which was found to be in the range 14.32 to 33.35 nm.Hall measurements indicate that the films were p-type,having carrier concentration≅ 10 17 cm -3 and Hallmobility (0.42 - 7.10)× 10 3 cm 2 /Vs for the film thicknessof 300 nm. It is observed that the carrier concentrationdecreases and Hall mobility increases with the increaseof substrate temperature. The sheet resistance is foundto decrease with the increase of substrate temperature.The Hall mobility decreased with the increase of the filmthickness and the maximum Hall mobility of 1.34 × 10 4cm2 /Vs was obtained for the films the thickness of 1000nm and the substrate temperature of 473K.